Thin film transistor array panel and method for manufacturing the same

ABSTRACT

A thin film transistor panel includes a substrate, a gate line extending in a first direction on the substrate, a data line disposed on the substrate, the data line crossing the gate line with an insulation layer therebetween and extending in a second direction, a thin film transistor including a control terminal connected to the gate line, an input terminal connected to the data line, and an output terminal, a color filter disposed on the thin film transistor, the color filter having an opening corresponding to the output terminal of the thin film transistor, a light blocking member disposed in the opening of the color filter, the light blocking member exposing a first region of a first end portion of the output terminal of the thin film transistor and having an output terminal light blocking portion enclosing the circumference of the first region, and a pixel electrode disposed on the light blocking member and the color filter, the pixel electrode contacting the first region of the output terminal.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from and the benefit of Korean PatentApplication No. 10-2008-0034876, filed on Apr. 15, 2008, which is herebyincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a thin film transistor array panel anda manufacturing method thereof.

2. Discussion of the Background

Liquid crystal displays (LCDs) are one of the most widely used flatpanel displays, and an LCD includes a pair of panels provided withfield-generating electrodes, such as pixel electrodes and a commonelectrode, and a liquid crystal (LC) layer disposed between the twopanels. The LCD displays images when voltages are applied to thefield-generating electrodes to generate an electric field in the LClayer that determines the orientations of LC molecules therein to adjustpolarization of incident light.

This liquid crystal display also includes a color filter to displaycolors using light transmitted to the liquid crystal layer, and thecolor filter is generally disposed on a display panel having a commonelectrode. Since the color filter commonly includes red, green, and bluecolors, the color filter should be aligned to face the correspondingpixels when aligning the two display panels. However, because the areaof the light blocking member defining the openings corresponding to thepixels may be wide in consideration of a misalignment margin, the sizeof the openings may be decreased such that the aperture ratio of thepixels may be reduced.

To solve this problem, techniques in which the color filters are formedon the display panel having thin film transistors have been provided.When the color filter is formed on the thin film transistor array panel,a portion of the color filter should be removed to form a contact holethrough which the pixel electrode may be connected to a drain electrodeof the thin film transistor, and the side wall of the color filter maybe formed with a smooth incline. However, the arrangement of the LCmolecules may be abnormally distorted by the inclined portion, therebygenerating light leakage. To block the light leakage, the drainelectrode may be formed to be wide, but this may deteriorate theaperture ratio.

SUMMARY OF THE INVENTION

The present invention provides a thin film transistor array panel thatmay provide for an improved aperture ratio.

The present invention also provides a method of manufacturing the thinfilm transistor.

Additional features of the invention will be set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention.

The present invention also discloses a thin film transistor panelincluding a substrate, a gate line extending in a first direction on thesubstrate, a data line disposed on the substrate, the data line crossingand insulated from the gate line and extending in a second direction, athin film transistor, which includes a control terminal connected to thegate line, an input terminal connected to the data line, and an outputterminal, a color filter disposed on the thin film transistor, the colorfilter having an opening corresponding to the output terminal of thethin film transistor, a light blocking member disposed in the opening ofthe color filter, the light blocking member exposing a first region of afirst end portion of the output terminal of the thin film transistor andhaving an output terminal light blocking portion enclosing the firstregion, and a pixel electrode disposed on the light blocking member andthe color filter, the pixel electrode contacting the first region of theoutput terminal.

The present invention also discloses a method for manufacturing a thinfilm transistor array panel including forming a gate line extending in afirst direction, forming a gate insulating layer on the gate line,forming a semiconductor on the gate insulating layer, forming a dataline, which extends in a second direction crossing the first direction,and a drain electrode, forming a passivation layer on the data line andthe drain electrode, forming a color filter on the passivation layer,the color filter having an opening exposing a first end portion of thedrain electrode, forming a drain electrode light blocking memberexposing a first region of the first end portion of the drain electrodeand enclosing a circumference of the first region in the opening of thecolor filter, forming an overcoat on the color filter and the drainelectrode light blocking member, forming a contact hole exposing thefirst region of the drain electrode by photolithography of the overcoatand the passivation layer, and forming a pixel electrode connected tothe drain electrode through the contact hole.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with the description serve to explain the principles of theinvention

FIG. 1 is a layout view of a thin film transistor array panel accordingto an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1.

FIG. 3 is a cross-sectional view taken along line III-III of FIG. 1.

FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 1.

FIG. 5 is a layout view only showing a light blocking member in the thinfilm transistor array panel shown in FIG. 1.

FIG. 6 is layout view enlarging the cross-sectional of one side of thedrain electrode in the thin film transistor array panel according to anexemplary embodiment of the present invention.

FIG. 7 and FIG. 8 are cross-sectional views showing intermediate stepsin a manufacturing process of the thin film transistor array panelaccording to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The invention is described more fully hereinafter with reference to theaccompanying drawings, in which embodiments of the invention are shown.This invention may, however, be embodied in many different forms andshould not be construed as limited to the embodiments set forth herein.Rather, these embodiments are provided so that this disclosure isthorough, and will fully convey the scope of the invention to thoseskilled in the art. In the drawings, the size and relative sizes oflayers and regions may be exaggerated for clarity. Like referencenumerals in the drawings denote like elements.

It will be understood that when an element or layer is referred to asbeing “on” or “connected to” another element or layer, it can bedirectly on or directly connected to the other element or layer, orintervening elements or layers may be present. In contrast, when anelement is referred to as being “directly on” or “directly connected to”another element or layer, there are no intervening elements or layerspresent.

Now, a thin film transistor array panel according to an exemplaryembodiment of the present invention will be described in detail. FIG. 1is a layout view of a thin film transistor array panel according to afirst exemplary embodiment of the present invention, and FIG. 2, FIG. 3,and FIG. 4 are cross-sectional views taken along lines II-II, III-III,and IV-IV of FIG. 1, respectively.

In a thin film transistor array panel according to an exemplaryembodiment of the present invention, a plurality of gate lines 121 and aplurality of storage electrode lines 131 are formed on an insulationsubstrate 110, which may be made of transparent glass.

The gate lines 121 transmit gate signals and extend substantially in atransverse direction. Each gate line 121 includes a plurality ofprotrusions forming gate electrodes 124 a and 124 b, and an end portion129 having a large area for connection with another layer or an externaldriving circuit. The storage electrode lines 131 are disposed betweentwo adjacent gate lines 121 and extend substantially parallel to thegate lines 121 in the transverse direction, and receive a voltage suchas a common voltage Vcom that is applied to a common electrode. Thestorage electrode line 131 includes a plurality of protrusions forming aplurality of storage electrodes 137, and a plurality of branches 133 aand 133 b to prevent light leakage and increase the area of the storageline 131.

The gate lines 121 and the storage electrode lines 131 may have amulti-layered structure including two conductive layers (not shown)having different physical properties. One of the two conductive layersmay be made of a low resistivity metal, such as an Al-containing metal,a Ag-containing metal, or a Cu-containing metal, to reduce signal delayor voltage drop in the gate lines 121 and the storage electrode lines131. The other conductive layer may be made of a material, such as aMo-containing metal, Cr, Ti, or Ta, that has good contactcharacteristics with other materials such as indium tin oxide (ITO) andindium zinc oxide (IZO). As examples of these combinations, a chromiumlower layer and an aluminum or aluminum alloy upper layer, and analuminum or aluminum alloy lower layer and a molybdenum or a molybdenumalloy upper layer, may be formed. However, the gate lines 121 and thestorage electrode lines 131 may be made of various other metals orelectrical conductors.

Side surfaces of the gate lines 121 and the storage electrode lines 131are inclined to a surface of the substrate 110, and an inclination anglethereof may be about 30° to 80°.

A gate insulating layer 140, which may be made of silicon nitride(SiN_(x)) or silicon oxide (SiO_(x)), is formed on the gate lines 121and the storage electrode lines 131.

A plurality of semiconductor stripes 151 l and 151 r, which may be madeof hydrogenated amorphous silicon (a-Si) or polysilicon, are formed inpairs on the gate insulating layer 140. The semiconductor stripes 151 land 151 r substantially extend in a vertical direction, and include aplurality of protrusions 154 a and 154 b respectively extending towardthe gate electrodes 124 a and 124 b.

A plurality of ohmic contact stripes 161 l and 161 r and islands 165 aand 165 b are formed on the semiconductor stripes 151 l and 151 r. Theohmic contact stripes 161 l and 161 r and islands 165 a and 165 b may bemade of a material such as n+hydrogenated amorphous silicon in which ann-type impurity such as phosphorus is doped with a high concentration,or silicide. The ohmic contact stripes 161 l and 161 r respectivelyinclude a plurality of protrusions 163 a and 163 b, and the protrusions163 a and 163 b and the ohmic contact islands 165 a and 165 b are formedin pairs and are disposed on the protrusions 154 a and 154 b of thesemiconductor stripes 151 l and 151 r, respectively.

The semiconductors 151 l and 151 r and the ohmic contacts 161 l, 161 r,165 a, and 165 b are inclined with respect to a surface of the substrate110, and an inclination angle thereof is about 30° to 80°.

A plurality of left and right data lines 171 l and 171 r and a pluralityof first and second drain electrodes 175 a and 175 b are formed on theohmic contacts 161 l, 161 r, 165 a, and 165 b. Here, the ohmic contactstripes 161 l and 161 r, and the semiconductor stripes 151 l and 151 r,are disposed under the left data lines 171 l and the right data lines171 r, respectively.

The data lines 171 l and 171 r transmit data voltages, and extendsubstantially in a vertical direction while crossing the gate lines 121and the storage electrode lines 131. Each data line 171 l and 171 rincludes a plurality of source electrodes 173 a and 173 b curved towardthe gate electrodes 124 a and 124 b and having a “U” shape, and endportions 179 l and 179 r to connect to other layers or an externaldriving circuit.

The drain electrodes 175 a and 175 b are respectively spaced apart fromthe data lines 171 l and 171 r, and face the source electrode 173 a and173 b with respect to the gate electrodes 124 a and 124 b. Each drainelectrode 175 a and 175 b includes a first end portion connected torespective sub-pixel electrodes 191 a and 191 b and having a wide area,and a second end portion having a bar shape. The second end portions ofthe drain electrodes 175 a and 175 b are enclosed by the sourceelectrodes 173 a and 173 b with the “U” shape, respectively.

The gate electrodes 124 a and 124 b, the source electrodes 173 a and 173b, and the drain electrodes 175 a and 175 b respectively form thin filmtransistors Qa and Qb along with the semiconductors 154 a and 154 b, andthe channels of the thin film transistors Qa and Qb are formed in thesemiconductors 154 a and 154 b between the source electrodes 173 a and173 b, and the drain electrodes 175 a and 175 b.

The data lines 171 l and 171 r and the drain electrodes 175 a and 175 bmay have a multi-layered structure including a refractory metal layer(not shown) and a low resistance conductive layer (not shown)

A multi-layered structure may include, for example, a dual-layerincluding a lower layer of chromium, molybdenum, or an alloy thereof andan aluminum or aluminum alloy upper layer, or a triple-layer including amolybdenum or molybdenum alloy lower layer, an aluminum or aluminumalloy middle layer, and a molybdenum or molybdenum alloy upper layer.However, the data lines 171 l and 171 r and the drain electrodes 175 aand 175 b may be made of various other metals or conductors.

Side surfaces of the data lines 171 l and 171 r and the drain electrodes175 a and 175 b may be inclined to the surface of the substrate 110 likethe gate lines 121 and the storage electrode lines 131, and theinclination angle thereof may be about 30° to 80°.

A passivation layer 180 is formed on the data lines 171 l and 171 r andthe drain electrodes 175 a and 175 b. The passivation layer 180 may bemade of silicon nitride or silicon oxide.

A plurality of color filters 230 are formed on the passivation layer180. The color filters 230 may each have one color of red, green, andblue. The color filters 230 may be formed with the same color in thelongitudinal direction between two data lines 171 l and 171 r, and thecolor filters 230 have a striped arrangement of the sequence of green,red, and blue in this case. Here, the height of the color filters 230may be in the range of about 1-3 μm. However, the arrangement of thecolor filters 230 may be changed in various ways to arrange thedifferent colors in each pixel.

The color filters 230 have a plurality of openings 231 and 232 exposingthe wide end portions of the drain electrodes 175 a and 175 b, aplurality of openings 233 exposing the storage electrodes 137, aplurality of openings 234 exposing the portion near the channels of thethin film transistors, and a plurality of openings 235 exposing theright and left data lines 171 l and 171 r. Here, the openings 233exposing the storage electrodes 137 reduce the distance between thestorage electrodes 137 and the pixel electrodes 190, and although thearea of the storage electrodes 137 is decreased, the storage capacitancegenerated therebetween may be sufficiently obtained. The openings 233may be omitted if necessary.

A light blocking member 220 is formed on the passivation layer 180. Thelight blocking member 220 is disposed in the openings 231, 232, 233,234, and 235 of the color filters 230. Accordingly, as shown in FIG. 5,the light blocking member 220 includes first portions 221 disposed onthe data lines 171 l and 171 r in the longitudinal direction, secondportions 223 a and 223 b disposed above and below the storage electrodelines 131, third portions 225 a and 225 b disposed near expanded endportions of the drain electrodes 175 a and 175 b, and fourth portions227 a and 227 b covering the channels of the thin film transistors Qaand Qb.

The first portions 221 cover the data lines 171 l and 171 r, and extendaccording to the data lines 171 l and 171 r in the longitudinaldirection. Specifically, the first portions 221 are disposed with astripe shape to define the space between the color filters 230 of thedifferent colors. The second portions 223 a and 223 b are disposed aboveand below the storage electrodes 137, and are formed parallel to thestorage electrodes 137 in the transverse direction such that they areconnected between the first portions 221. The third portions 225 a and225 b are disposed on the end portions of the drain electrodes 175 a and175 b, and have a shape enclosing the end portions of the drainelectrodes 175 a and 175 b, when shown on a plane surface. The shapes ofthe third portions 225 a and 225 b may vary, and for example, may be aquadrangle shape as shown in FIG. 1, an octagonal shape, or a circularshape.

In this way, because the first portions 221 extend in the longitudinaldirection, the light leakage generated near the data lines 171 l and 171r may be blocked. Also, the second portions 223 a and 223 b are disposedadjacent to the storage electrodes 137. Thus, the area where the liquidcrystal cell gap becomes non-uniform due to the opening 233 of the colorfilter 230 exposing the storage electrode 137 may be decreased, and thelight blocking member blocks the light leakage generated near thestorage electrode such that the area of the storage electrode may bereduced, which may improve the aperture ratio. Also, the third portions225 a and 225 b are formed on a portion where contact holes 185 a and185 b, through which the drain electrodes 175 a and 175 b are connectedto pixel electrodes, are disposed such that the area where the liquidcrystal cell gap becomes non-uniform near the contact holes may bereduced, and the light blocking member blocks the light leakagegenerated near the contact holes such that the area of the drainelectrode may be reduced, which may improve the aperture ratio.

The light blocking member 220 further includes the fourth portions 227 aand 227 b disposed on the thin film transistors Qa and Qb. The fourthportions 227 a and 227 b prevent light from being incident to thechannels of the thin film transistors Qa and Qb. In the FIGs., thefourth portions 227 a and 227 b are spaced apart from the first portions221 and have an island shape, but they may be connected to the firstportions 221.

Here, the height of the light blocking member 220 may be almost the sameas that of the color filters 230, however if the height of the lightblocking member 220 is less than 1.5 μm, the ability of the lightblocking member 220 to prevent the light transmission may bedeteriorated. Accordingly, the height of the light blocking member 220should be more than 1.5 μm. The width of the light blocking member 220may vary, however if the width of the light blocking member 220 is verynarrow, light leakage may occur, and if the width thereof is very wide,the aperture ratio may be deteriorated. Therefore, an appropriate widthis required. The width of the light blocking member 220, particularlythe width of the third portions 225 a and 225 b, will be described belowin detail with reference to FIG. 6.

An overcoat 250 is formed on the light blocking member 220 and the colorfilters 230. The overcoat 250 is formed on the passivation layer 180covering the storage electrodes 137 between the second portions 223 aand 223 b. The overcoat 250 is removed on the third portions 225 a and225 b of the light blocking member 220, thereby exposing the thirdportions 225 a and 225 b. Accordingly, contact between the overcoat 250and the passivation layer 180 in the active region is prevented. Whenthe overcoat 250 and the passivation layer 180 contact each other, theovercoat 250 may be lifted due to adhesion stress between the twolayers, and preventing this may improve the process yield. The overcoat250 may be made of an inorganic insulating material such as siliconoxide, silicon nitride, or an organic insulating material.

The overcoat 250 and the passivation layer 180 have a plurality ofcontact holes 182 l, 182 r exposing the end portions 179 l and 179 r ofthe data lines 171 l and 171 r, respectively, and the passivation layer180 has a plurality of contact holes 185 a and 185 b exposing the endportions of the drain electrodes 175 a and 175 b. Also, the overcoat250, the passivation layer 180, and the gate insulating layer 140 have aplurality of contact holes 181 exposing the end portions 129 of the gatelines 121. The contact holes 185 a and 185 b are disposed inside thethird portions 225 a and 225 b, and are formed by simultaneously etchingthe overcoat 250 and the passivation layer 180.

A plurality of first and second sub-pixel electrodes 191 a and 191 b anda plurality of contact assistants 81, 82 l, and 82 r are formed on theovercoat 250. They may be made of a transparent conductive material suchas ITO or IZO.

The first sub-pixel electrode 191 a and the second sub-pixel electrode191 b are connected to the drain electrodes 175 a and 175 b through thecontact holes 185 a and 185 b, respectively, and the data voltage isapplied from the drain electrodes 175 a and 175 b to the first andsecond pixel electrodes 191 a and 191 b.

Two sub-pixel electrodes 191 a and 191 b applied with the data voltagesgenerate an electric field along with the common electrode to determinethe orientation of liquid crystal molecules of the liquid crystal layerdisposed between the electrodes 191 and 270. Here, because the firstsub-pixel electrodes 191 a receive the data voltages through the leftdata lines 171 l and the second sub-pixel electrodes 191 b receive thedata voltages through the right data lines 171 r, different voltages maybe applied thereto. In this way, if the different voltages are applied,the arrangement of the liquid crystal of the corresponding regionsbecomes different. Accordingly, when the voltages applied to the firstand second sub-pixel electrodes 191 a and 191 b are appropriatelyadjusted, it may be possible to make an image viewed from the sideappear as similar as possible to an image viewed from the front. Thatis, it may be possible to improve the side visibility of the liquidcrystal display. Here, the absolute value of the voltage applied to thefirst sub-pixel electrode 191 a having a wider area among the firstsub-pixel electrodes 191 a and the second sub-pixel electrodes 191 bshould be higher than the absolute value of the voltage applied to thesecond sub-pixel electrodes 191 b in order to improve the sidevisibility.

The first sub-pixel electrodes 191 a have a plurality of cutouts, andthe cutouts and a gap 94 between the first sub-pixel electrodes 191 aand the second sub-pixel electrodes 191 b generate horizontal componentsof the electric field along with cutouts of a common electrode (notshown) formed on a display panel (not shown) facing the thin filmtransistor array panel or protrusions (not shown) formed on the commonelectrode to control the arrangement operation of the liquid crystal.

The sub-pixel electrodes 191 a and 191 b and the common electrode form acapacitor (hereinafter referred to as “liquid crystal capacitor”) tomaintain the applied voltage even after the thin film transistor isturned off. To enhance the voltage storage capacity, a storage capacitorcoupled to the liquid crystal capacitor in parallel is formed byoverlapping the first and second sub-pixel electrodes 191 a and 191 b,and the storage electrode lines 131. Here, because the color filters 230are not present between the storage electrodes 137 and the first andsecond sub-pixel electrodes 191 a and 191 b, the capacitance of thestorage capacitor may be increased. If the capacitance of the storagecapacitor is small, the second portions 223 a and 223 b of the lightblocking member 220 may be omitted. In this case, the color filters 230are disposed between the first and second sub-pixel electrodes 191 a and191 b, and the storage electrode 137, which may the capacitance of thestorage capacitor. A kick-back voltage may be increased due to thereduction of the storage capacitance, but this may be solved bydecreasing the size of the thin film transistor to reduce the parasiticcapacitance generated between the gate electrode and the drain electrodethereof, or by using a liquid crystal material having a large dielectricratio to increase the liquid crystal capacitance.

A pair of first and second subpixel electrodes 191 a and 191 b formingone pixel electrode are engaged with each other with the gap 94therebetween. The shape of the pixel electrodes 191 may vary.

Next, the width (or diameter) of the third portions 225 a and 225 b ofthe light blocking member and the width (or diameter) of the end portionof the drain electrode 175 a and 175 b will be described with referenceto FIG. 6, in relation to the width (or diameter) of the removal regionsof the light blocking member forming the contact holes 185 a and 185 b.Here, the diameter is applied to the case in which at least one of thethird portions 225 a and 225 b of the light blocking member, the endportion of the drain electrode, and the removal region of the lightblocking member is a circular shape, as indicated by the dotted line inFIG. 6.

As above-described, according to an exemplary embodiment of the presentinvention, the third portions 225 a and 225 b are formed on thecircumference of the drain electrodes 175 a and 175 b such that the areaof the drain electrodes 175 a and 175 b may be reduced, which mayimprove the aperture ratio. However, this effect may be gained withoutconsidering the error margin provided by considering the processcapacity of the exposure device and the inclined surface of the colorfilter 230 formed due to the opening in the case in which the thirdportions 225 a and 225 b are not formed. When the third portions 225 aand 225 b are not formed, the interval between the contact hole and theopening of the color filter may be about 3um, and the interval from theopening of the color filter to the edge of the end portion of the drainelectrode may be about 6 um. However, as in the exemplary embodiment ofthe present invention, the third portions 225 a and 225 b are formed onthe drain electrodes 175 a and 175 b such that the drain electrodes 175a and 175 b may be formed with almost the same or less area than that ofthe opening of the color filter 230. In an exemplary embodiment of thepresent invention, the width (or diameter) of the contact holes 185 aand 185 b may be in the range of 5-25 μm, the width (or diameter) of thedrain electrodes 175 a and 175 b may be in the range of 5-35 μm, and thewidth (or diameter) of the third portions 225 a and 225 b may be in therange of 15-60 μm in consideration of the align error of the exposuredevice. Here, the third portions 225 a and 225 b of the light blockingmember 220 are somewhat wider than the drain electrodes 175 a and 175 bsuch that it may be possible for the third portions 225 a and 225 b ofthe light blocking member 220 to cover the boundaries of the drainelectrodes 175 a and 175 b.

Next, the manufacturing method of the thin film transistor array panelincluding these elements will be described in detail.

FIG. 7 and FIG. 8 are cross-sectional views showing the intermediatesteps in the manufacturing process of the thin film transistor arraypanel according to an exemplary embodiment of the present invention.

Firstly, as shown in FIG. 1 and FIG. 7, a metal layer such asaluminum-neodymium (AlNd) or molybdenum (Mo) is deposited on aninsulation substrate 110 and patterned by photolithography to form agate line 121 including gate electrodes 124 a and 124 b and an endportion 129, a storage electrode line 131 including branches 133 a and133 b, and a storage electrode 137.

Next, a gate insulating layer 140 is formed on the gate line 121 and thestorage electrode line 131, a semiconductor layer, an ohmic contactlayer, a data metal layer, and a photoresist film are sequentiallydeposited, and the photoresist film is patterned by a photo processusing a half-tone mask to form a photoresist film pattern havingdifferent thicknesses in different regions. Here, in the photoresistfilm pattern, the thickness of a region corresponding to the portionwhere the data lines 171 l and 171 r and the drain electrodes 175 a and175 b is thick, and the thickness of a region corresponding to a portionbetween the source electrodes 173 a and 173 b and the drain electrodes175 a and 175 b is thin. Next, the data metal layer, the ohmic contactlayer, and the semiconductor layer are etched by using the photoresistfilm pattern as an etch mask to form a preliminary data line, apreliminary ohmic contact, and a plurality of semiconductor stripes 151l and 151 r (see FIG. 3), and the photoresist film pattern is ashed toremove a thin portion among the photoresist film pattern correspondingto the portion between the source electrodes 173 a and 173 b, and thedrain electrodes 175 a and 175 b. The preliminary data line and thepreliminary ohmic contact are then etched using the ashed photoresistfilm pattern as an etch mask to form a plurality of data lines 171 l and171 r and a plurality of drain electrodes 175 a and 175 b, and aplurality of ohmic contacts 161 l, 161 r, 165 a, and 165 b thereunder.

Next, a passivation layer 180 is formed on the data lines 171 l and 171r and the drain electrodes 175 a and 175 b.

Then, a photoresist including pigments is repeatedly coated, exposed,and developed to form color filters 230 including a plurality ofopenings 231, 232, 233, 234, and 235.

A photoresist including the dispersed black color pigments is thencoated, exposed, and developed to form a light blocking member 220including the first portion 221, the second portions 223 a and 223 b,the third portions 225 a and 225 b, and the fourth portions 227 a and227 b in the openings 231, 232, 233, 234, and 235 of the color filters230. When forming the light blocking member 220 made of an organicmaterial without photosensitivity, the light blocking member 220 ispatterned by photolithography.

An overcoat 250 is formed on the color filter 230 and the light blockingmember 220.

Next, as shown in FIG. 8, a photoresist film pattern PR exposing theovercoat 250 on the third portions 225 a and 225 b of the light blockingmember 220 is formed on the overcoat 250, and the overcoat 250 and thepassivation layer 180 are sequentially patterned by photolithography toform contact holes 185 a and 185 b on a portion enclosing the thirdportions 225 a and 225 b. Here, the overcoat 250 on the third portions225 a and 225 b is removed such that the overcoat 250 and thepassivation layer 180 are prevented from contacting each other.

The first and second subpixel electrodes 191 a and 191 b, and thecontact assistants 81, 82 l, and 82 r, are then formed on the overcoat250 (see FIG. 1).

According to an exemplary embodiment of the present invention, the lightblocking member encloses the contact holes such that the area where theliquid crystal cell gap on the circumference of the contact holesbecomes non-uniform may be decreased, and the light blocking memberprevents the light leakage generated at the circumference of the contactholes such that the area of the drain electrode may be decreased, whichmay improve the aperture ratio.

Also, according to an exemplary embodiment of the present invention,when the color filter on the storage electrode is removed tosufficiently form the storage capacitance, the light blocking member isformed on the circumference of the storage electrode such that the areawhere the liquid crystal cell gap becomes non-uniform may be decreased,and the light blocking member may prevent light leakage near the storageelectrode such that the storage electrode has a narrow area, which mayimprove the aperture ratio.

It will be apparent to those skilled in the art that variousmodifications and variation can be made in the present invention withoutdeparting from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A thin film transistor array panel, comprising: a substrate; a gateline extending in a first direction on the substrate; a data linedisposed on the substrate, the data line crossing and insulated from thegate line and extending in a second direction; a thin film transistorcomprising a gate electrode connected to the gate line, a sourceelectrode connected to the data line, and a drain electrode; a colorfilter disposed on the thin film transistor, the color filter comprisingan opening corresponding to the drain electrode of the thin filmtransistor; a light blocking member, comprising a drain electrode lightblocking portion disposed in the opening of the color filter, exposing afirst region of a first end portion of the drain electrode of the thinfilm transistor and enclosing a circumference of the first region; and apixel electrode disposed on the light blocking member and the colorfilter, the pixel electrode contacting the first region of the drainelectrode.
 2. The thin film transistor array panel of claim 1, furthercomprising an overcoat comprising an inorganic insulating materialarranged between the color filter and the pixel electrode and betweenthe light blocking member and the pixel electrode.
 3. The thin filmtransistor array panel of claim 2, further comprising a passivationlayer comprising an inorganic insulating material arranged between thecolor filter and the thin film transistor and between the light blockingmember and the thin film transistor.
 4. The thin film transistor arraypanel of claim 3, wherein the drain electrode light blocking portioncovers a boundary of the first end portion of the drain electrode. 5.The thin film transistor array panel of claim 4, wherein a width orradius of the first region is in the range of 5-25 μm, a width or radiusof the first end portion of the drain electrode is in the range of 5-35μm, and a width or radius of the drain electrode light blocking portionis in the range of 15-60 μm.
 6. The thin film transistor array panel ofclaim 5, wherein the light blocking member further comprises a signalline portion extending along the data line, and the color filter isdivided into two regions by the signal line portion, the two regionshaving different colors from each other.
 7. The thin film transistorarray panel of claim 6, further comprising a storage electrode lineextending in the first direction and comprising a storage electrode,wherein the light blocking member further comprises a storage electrodelight blocking portion enclosing at least a portion of the storageelectrode along with the signal line portion.
 8. The thin filmtransistor array panel of claim 7, wherein the light blocking memberfurther comprises a thin film transistor portion covering the thin filmtransistor.
 9. The thin film transistor array panel of claim 1, whereinthe drain electrode light blocking portion covers the boundary of thefirst end portion of the drain electrode.
 10. The thin film transistorarray panel of claim 9, wherein a width or radius of the first region isin the range of 5-25 μm, a width or radius of the first end portion ofthe drain electrode is in the range of 5-35 μm, and a width or radius ofthe drain electrode light blocking portion is in the range of 15-60 μm.11. The thin film transistor array panel of claim 1, wherein the dataline comprises a first data line and a second data line; the thin filmtransistor comprises a first thin film transistor having a first sourceelectrode connected to the first data line and a second thin filmtransistor having a second source electrode connected to the second dataline; and the pixel electrode comprises a first subpixel electrodeconnected to a first drain electrode of the first thin film transistor,and a second subpixel electrode connected to a second drain electrode ofthe second thin film transistor.
 12. The thin film transistor arraypanel of claim 11, wherein the drain electrode light blocking portion ofthe light blocking member comprises a first drain electrode lightblocking portion enclosing the first drain electrode of the first thinfilm transistor, and a second drain electrode light blocking portionenclosing the second drain electrode of the second thin film transistor.